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Mononeuropathy multiplex with ulcerative colitis.

We describe acute mononeuropathy multiplex in a patient with chronic ulcerative colitis. The symptoms of neuropathy were well correlated with the disease activity of colitis. Both electrophysiological study and sural nerve biopsy revealed axonal degeneration. Mononeuropathy multiplex may be an extraintestinal manifestation of ulcerative colitis.

Adult↗

Protein microarrays and multiplexed sandwich immunoassays: what beats the beads?

Protein microarray technology allows the simultaneous determination of a large variety of parameters from a minute amount of sample within a single experiment. Assay systems based on this technology are currently applied for the identification, quantitation and functional analysis of proteins. Protein microarray technology is of major interest for proteomic research in basic and applied biology as well as for diagnostic applications. Miniaturized and parallelized assay systems have reached adequate sensitivity and hence have the potential to replace singleplex analysis systems. However, robustness and automation needs to be demonstrated before this technology will finally prove suitable for high-throughput applications. Miniaturized and parallelized sandwich immunoassays are the most advanced assays formats among the different protein microarray applications. Multiplexed sandwich immunoassays can be used for the identification of biomarkers and the validation of potential target molecules. In this review an overview will be given on the current stage of protein microarray technology with a special focus on miniaturized multiplexed sandwich immunoassays.

Automation↗

Use of a multiplex polymerase chain reaction assay in the antemortem diagnosis of toxoplasmosis and neosporosis in the central nervous system of cats and dogs.

OBJECTIVE: To develop a multiplex polymerase chain reaction (PCR) assay for the detection of Toxoplasma gondii and Neospora caninum DNA in canine and feline biological samples. SAMPLE POPULATION; Biological samples from 7 cats with systemic (n = 4) or CNS (3) toxoplasmosis, 6 dogs with neospora- or toxoplasma-associated encephalitis, and 11 animals with nonprotozoal disease. PROCEDURE: Primers for T gondii, N caninum, and the canine ferritin gene (dogs) or feline histone 3.3 gene (cats) were combined in a single PCR assay. The DNA was extracted from paraffin-embedded brain tissue, CSF, or skeletal muscle. The PCR products with positive results were cloned, and sequence identity was confirmed. RESULTS: Of 7 cats and 4 dogs with immunohistochemical or serologic evidence of toxoplasmosis, PCR results were positive for all cats and 3 dogs for T gondii, and positive for T gondii and N caninum for 1 dog. Another dog had negative PCR results for both parasites. Of 2 dogs with immunohistochemical or serologic evidence of neosporosis, PCR results were positive for 1 for N caninum and positive for the other for T gondii. All negative-control samples yielded negative results for T gondii and N caninum on the PCR assay. CONCLUSIONS AND CLINICAL RELEVANCE: Standard tests for toxoplasmosis or neosporosis associated with the CNS rely on serologic, histologic, or immunohistochemical analysis and can be difficult to interpret. The multiplex PCR assay with built-in control reactions could be a complementary clinical tool for the antemortem diagnosis of toxoplasmosis or neosporosis associated with the CNS.

Animals↗

Evaluation of a rapid single multiplex microsatellite-based assay for use in forensic genetic investigations in dogs.

OBJECTIVE: To develop a set of microsatellite markers, composed of a minimal number of these markers, suitable for use in forensic genetic investigations in dogs. SAMPLE POPULATION: Blood, tissue, or buccal epithelial cells from 364 dogs of 85 breeds and mixed breeds and 19 animals from related species in the family Canidae. PROCEDURE: 61 tetranucleotide microsatellite markers were characterized on the basis of number and size of alleles, ease of genotyping, chromosomal location, and ability to be coamplified. The range in allele size, number of alleles, total heterozygosity, and fixation index for each marker were determined by use of genotype data from 383 dogs and related species. Polymorphism information content was calculated for several breeds of dogs. RESULTS: 7 microsatellite markers could be coamplified. These markers were labeled with fluorescent dyes, multiplexed into a single reaction, and optimized for resolution in a commercial genetic analyzer. The multiplex set was used to identify sires for 2 mixed litters. The test was not species specific; genotype information collected for wolves, coyotes, jackals, New Guinea singing dogs, and an African wild dog could not distinguish between these species. CONCLUSIONS AND CLINICAL RELEVANCE: This set of 7 microsatellite markers is useful in forensic applications (ie, identification of dogs and determination of parentage) in closely related animals and is applicable to a wide range of species belonging to the family Canidae.

Animals↗

Detection of BCR-ABL transcripts by multiplex and nested PCR in different haematological disorders.

Single-step Multiplex RT-PCR was used as a rapid and highly sensitive method for screening patients with myeloproliferative conditions and ALL for the presence of underlying BCR-ABL gene fusions. Positive and negative results obtained with the multiplex assay were subsequently confirmed by nested PCR. We studied 21 patients for detecting the presence of b3a2, b2a2 and e1a2 BCR-ABL transcripts at diagnosis and following treatment with different therapeutical procedures. These studies allowed the molecular characterisation of patients with different haematological disorders and for demonstrating BCR-ABL transcripts in Ph-CML. In a Ph+ CML patient, a switch of isoforms was detected after bone marrow transplantation and infusion with donor lymphocytes, implying substitution of e1a2 for b3a2 coexisting with a myeloid/lymphoid biphenotypic profile. In ALL, one Ph+ patient showed coexpression of e1a2 and b2a2 at diagnosis followed by persistence of e1a2 after bone marrow transplantation. Our results were compared to previous findings in the literature on molecular diagnosis of leukaemias.

DNA, Complementary↗

Application of a multiplex PCR for the detection of protozoan pathogens of the eastern oyster Crassostrea virginica in field samples.

Populations of eastern oysters Crassostrea virginica along the east coast of North America have repeatedly experienced epizootic mass mortality due to infections by protozoan parasites, and molecular diagnostic methodologies are fast becoming more widely available for the diagnosis of protozoan diseases of oysters. In this study we applied a modified version of an existing multiplex polymerase chain reaction (PCR) for detection of the eastern oyster parasites Haplosporidium nelsoni, H. costale and Perkinsus marinus from field-collected samples. We incorporated primers for DNA quality control based on the large subunit ribosomal RNA (LSU rRNA) gene of C. virginica. The multiplex PCR (MPCR) simultaneously amplified genomic DNA of C. virginica, and cloned DNA of H. nelsoni, P. marinus and H. costale. In field trial applications, we compared the performance of the MPCR to that of the conventional diagnostic techniques of histopathological tissue examination and the Ray/Mackin fluid thioglycollate medium (RMFT) assay. A total of 530 oysters were sampled from 18 sites at 12 locations along the east coast of the United States from the Gulf of Mexico to southern New England. The modified MPCR detected 21% oysters with H. nelsoni, 2% oysters with H. costale, and 40% oysters with P. marinus infections. In comparison, histopathological examination detected H. nelsoni and H. costale infections in 6 and 0.8% oysters, respectively, and the RMFT assay detected P. marinus infection in 31% oysters. The MPCR is a more sensitive diagnostic assay for detection of H. nelsoni, H. costale, and P. marinus, and incorporation of an oyster quality control product limits false negative results.

Animals↗

A multiplex PCR method of detecting recombinant DNAs from five lines of genetically modified maize.

Seven lines of genetically modified (GM) maize have been authorized in Japan as foods and feeds imported from the USA. We improved a multiplex PCR method described in the previous report in order to distinguish the five lines of GM maize. Genomic DNA was extracted from GM maize with a silica spin column kit, which could reduce experimental time and improve safety in the laboratory and potentially in the environment. We sequenced recombinant DNA (r-DNA) introduced into GM maize, and re-designed new primer pairs to increase the specificity of PCR to distinguish five lines of GM maize by multiplex PCR. A primer pair for the maize intrinsic zein gene (Ze1) was also designed to confirm the presence of amplifiable maize DNA. The lengths of PCR products using these six primer pairs were different. The Ze1 and the r-DNAs from the five lines of GM maize were qualitatively detected in one tube. The specific PCR bands were distinguishable from each other on the basis of the expected length. The r-DNA could be detected from maize samples containing 0.5% of each of the five lines of GM maize. The sensitivity would be acceptable to secure the verification of non-GMO materials and to monitor the reliability of the labeling system.

DNA Primers↗

Multiplex neuritis in a patient with autoimmune hepatitis: a case report.

A 37-year old woman presented with a 9-year history of hepatitis of unknown origin and aminotransferases within a 3-fold upper limit of normal. Autoimmune hepatitis (AIH) was diagnosed on the basis of elevated aminotransferases, soluble liver antigen/liver pancreas (SLA/LP) autoantibodies and characteristic histology. Immunosuppressive therapy led to rapid normalization of aminotransferases. Two years later, the patient developed left sided hemisensory deficits under maintenance therapy of prednisolone and azathioprine (AZT). Later she developed right foot drop and paraesthesia in the ulnar innervation territory on both sides. Magnetic resonance imaging (MRI) and cerebral panangiography suggested cerebral vasculitis. Neurological investigation and electromyography disclosed multiplex neuritis (MN) probably due to vasculitis. Consistent with this diagnosis, autoantibodies to extractable nuclear antigens were detectable in serum. Immunosuppression was changed to oral 150 mg cyclophosphamide (CPM0) per day. Prednisolone was increased to 40 mg/d and then gradually tapered to 5 mg. Oral CPM was administered up to a total dose of 40 g and then substituted by 6 times of an intervall infusion therapy of CPM (600 mg/m(2)). Almost complete motoric remission was achieved after 3 mo of CPM. Sensibility remained reduced in the right peroneal innervation territory. Follow-up of cranial MRI provided stable findings without any new or progressive lesions. This is the first report of multiplex neuritis in a patient with autoimmune hepatitis.

Adult↗

Analysis of spontaneous, gamma ray- and ethylnitrosourea-induced hprt mutants in HL-60 cells with multiplex PCR.

AIM: To explore the molecular spectra and mechanism of human hypoxanthine guanine phosphoribosyl transferase (hprt) gene mutation induced by ethyluitrosourea (ENU) and (60)Co gamma-rays. METHODS: Independent human promyelocytic leukemia cells (HL-60) mutants at the hprt locus were isolated from untreated, ethyluitrosourea (ENU) and (60)Co gamma-ray-exposed cells, respectively, and verified by two-way screening. The genetic changes underlying the mutation were determined by multiplex polymerase chain reaction (PCR) amplification and electrophoresis technique. RESULTS: With dosage increased, survival rate of plated cell reduced (in the group with dosage of ENU with 100-200 micro g/ml, P<0.01; in the group with dosage of (60)Co gamma-ray with 2-4 Gy, P<0.05) and mutational frequency increased (in the group of ENU 12.5-200.0 micro g/ml, P<0.05; in the group of (60)Co gamma-ray with 1-4 Gy, P<0.05) significantly. In the 13 spontaneous mutants analyzed, 92.3 % of mutant clones did not show any change in number or size of exon, a single exon was lost in 7.7 %, and no evidence indicated total gene deletion occurred in nine hprt exons. However, deletions were found in 79.7 % of ENU-induced mutations (62.5-89.4 %, P<0.01) and in 61.7 % of gamma-ray-induced mutations (28.6-76.5 %, P<0.01). There were deletion mutations in all 9 exons of hprt gene and the most of induced mutations were chain deletion with multiplex exons (97.9 % in gamma-ray-induced mutants, 88.1 % in ENU-induced mutants). CONCLUSION: The spectra of spontaneous mutations differs completely from that induced by EUN or (60)Co gamma-ray. Although both ENU and gamma-ray can cause destruction of genetic structure, mechanism of mutagenesis between them may be different.

Alkylating Agents↗

Ophthalmologic findings associated with arthrogryposis multiplex congenita: case report and review of the literature.

Arthrogryposis multiplex congenita is a birth defect characterized by multiple joint deformities and sometimes associated with various other congenital anomalies. There have been several reported cases of miscellaneous ocular abnormalities in conjunction with this syndrome. We report the first case of congenital ophthalmoplegia as well as juvenile onset glaucoma associated with arthrogryposis multiplex congenita. This case represented a unique therapeutic dilemma in that it was extremely difficult to surgically treat the patient's glaucoma because of her severe restrictions of ocular motility.

Adult↗

Multiplex PCR on leptospiral isolates from Kolenchery, Kerala, India.

Human leptospirosis causes severe multiorgan dysfunctions that may end in multiorgan failure and death. The methods in hand for diagnosis of leptospirosis like culture, ELISA and MAT only help to confirm the disease, and are of little value in early detection. The aim of this study was to find out if the two sets of primers described earlier could detect all the isolates from the area, for the purpose of using the resultant database for early detection of leptospires in future from clinical specimens. The study was done on culture isolates from Jan 2000 to June 2002 attending the department of medicine, MOSC medical college hospital, Kolenchery, Kerala, India. DNA of 45 culture isolates were amplified by multiplex PCR using two sets of previously described primers, G1, G2 and B 64-I, B 64-II. Specific amplifications of either 285 or 563 bp size were obtained from all isolates included in the study indicating the utility of the multiplex PCR in the rapid detection of leptospires in clinical samples.

DNA Primers↗

Multiplex polymerase chain reaction amplification and differentiation of Entamoeba histolytica and Entamoeba dispar DNA from stool samples.

Due to the clinical importance of differentiating the two species of the Entamoeba histolytica/Entamoeba dispar complex, we developed a multiplex polymerase chain reaction (PCR) method that overcomes time-consuming and laborious procedures. We report here a DNA extraction protocol using non-fixed stool samples that avoid long lysis-incubation periods through the combined use of zirconium beads and a lysis-supporting buffer. We characterized 49 of 52 stool specimens from Cuban patients with amoebiosis. Among them, 36 (75.5%) were infected only with E. dispar (the nonpathogenic species), while 13 (24.5%) displayed a mixed infection with both E. dispar and E. histolytica. The multiplex PCR protocol showed a specificity of 1.00 and a sensitivity of 0.94. Furthermore, the entire procedure can be performed in one day. This approach is therefore reliable and applicable in the field for epidemiologic studies.

Animals↗

Use of a multiplex PCR system for the simultaneous detection of heat labile toxin I and heat stable toxin II genes of enterotoxigenic Escherichia coil in skim milk and porcine stool.

Enterotoxigenic Escherichia coli (ETEC) strains which produce heat labile and/or heat stable toxins (LT and ST) may cause diarrhea in humans and farm animals. Using PCR primers specific for the LT I and ST II genes, a multiplex PCR system which allows detection of LT 1-and ST 11-producing ETEC strains was developed. When skim milk was used for a PCR assay, it was found that if target cells in the sample were precultured in MacConkey broth for 8 h prior to PCR as few as 10(0) cells per ml of the sample could be detected. Without the preculture step, 10(4) CFU of target cells per 0.2 g of porcine stool specimen were required to generate visible PCR products. The multiplex PCR system can be used for rapid testing of fecal specimens, food and possibly environmental samples for the presence of ETEC strains.

Animals↗

A multiplex polymerase chain reaction for the differentiation of Campylobacter jejuni and Campylobacter coli from a swine processing facility and characterization of isolates by pulsed-field gel electrophoresis and antibiotic resistance profiles.

A multiplex polymerase chain reaction (PCR) was developed for the detection and speciation of 60 Campylobacter strains isolated from porcine rectal swabs and from different areas in a pork processing plant. The PCR assay was based on primers specific for the cadF gene of pathogenic Campylobacter species, a specific but undefined gene of Campylobacter jejuni, and the ceuE gene of Campylobacter coli. Further characterization of these isolates was established by pulsed-field gel electrophoresis (PFGE) analyses with the restriction endonuclease SmaI. In addition to molecular discrimination, the antibiotic resistance profiles of the isolates were examined by the Kirby Bauer disc diffusion method with 22 antibiotics. Differentiation of isolates by multiplex PCR identified 86.9% (52 of 60) as C. coli and 13.1% (8 of 60) as C. jejuni. Using the Molecular Analyst software, 60 PFGE types were identified. The percentages of relatedness among C. jejuni strains with PFGE ranged from 25 to 86%, while those among C. coli strains ranged from 34 to 99%. Among the 60 PFGE types, each of 12 C. coli isolates showed > or =90% similarity to one other isolate. The antibiotic resistance profiles of all 60 isolates were distinct. Analyses of antibiotic resistance profiles showed that all isolates were resistant to five or more antibiotics. Twenty-five percent (2 of 8) of C. jejuni isolates and 15% (8 of 52) of C. coli isolates were resistant to at least one of the three fluoroquinolones tested, antibiotics that are commonly used in the treatment of human Campylobacter infections. Three percent (2 of 60) of Campylobacter isolates examined were resistant to all three fluoroquinolones. On the basis of the PFGE and antibiotic resistance profiles, each of the 60 isolates was distinct, suggesting that C. jejuni and C. coli strains originating from diverse sources were present in porcine samples and in the pork processing plant.

Animals↗

Development of two multiplex polymerase chain reactions for the detection of enterotoxigenic strains of Staphylococcus aureus isolated from foods.

Two multiplex polymerase chain reactions were developed for the detection of enterotoxigenic strains of Staphylococcus aureus: one multiplex reaction for the simultaneous detection of enterotoxigenic strains type A (entA), type B (entB), and type E (entE) and another for the simultaneous detection of enterotoxigenic strains type C (entC) and type D (entD). Both reactions were standardized with the use of the reference enterotoxigenic strains of S. aureus: FRI 722, producer of staphylococcal enterotoxin (SE) type A (SEA); FRI 1007, producer of SEB; FRI 137, producer of SEC1; FRI 472, producer of SED; and FRI 326, producer of SEE. Optimized methods were used to determine the presence of enterotoxigenic types for 51 S. aureus strains isolated from meat (sausage, ham, and chorizo) and dairy (powdered milk and cheese) products by the Baird-Parker technique. The enterotoxigenic capacities of the strains were determined by the indirect enzyme-linked immunosorbent assay (ELISA) with the use of reference staphylococcal toxins and antitoxins. Fifty of the 51 strains isolated were enterotoxigenic and produced one to four enterotoxin types, with the most frequently produced types being SEA and SED. Levels of correlation between the presence of genes that code for the production of SE (as determined by polymerase chain reaction) and the expression of these genes (as determined by the indirect ELISA) were 100% for SEA and SEE, 86% for SEC, 89% for SED, and 47% for SEB.

Animals↗

Simultaneous detection of Escherichia coli O157:H7, Salmonella, and Shigella in apple cider and produce by a multiplex PCR.

With three pairs of primers, a multiplex PCR assay was established for the simultaneous detection of Escherichia coli 0157:H7, Salmonella, and Shigella. Under the optimized conditions, the assay yielded a 252-bp product from E. coli O157:H7, a 429-bp product from Salmonella Typhimurium, and a 620-bp product from Shigella flexneri, respectively. When the DNA extraction of multiple target organisms was included in the same reaction, two or three corresponding amplicons of different sizes were observed. In the specificity test, 10 E. coli O157:H7 strains and one E. coli O157:NM strain showed the expected 252-bp amplicon. Seven other E. coli strains yielded no signal. Additionally, the 429-bp amplicon was produced from 20 Salmonella strains covering 16 serotypes, whereas the 620-bp amplicon was generated from 11 Shigella strains covering 4 species. No nonspecific amplification was observed with DNA from 48 other bacterial strains. Following a 24-h enrichment, the developed assay could concurrently detect the three pathogens at initial inoculation levels of approximately 8 x 10(-1) CFU/g (or CFU/ml) in apple cider, cantaloupe, lettuce, tomato, and watermelon and 8 x 10(1) CFU/g in alfalfa sprouts. The whole procedure can be easily completed within 30 h. The multiplex PCR assay can potentially be a simple, rapid, and efficient tool for presumptive and simultaneous screening of apple cider and produce for contamination by E. coli O157:H7, Salmonella, and/or Shigella.

Beverages↗

Multiplex PCR method for the simultaneous detection of histamine-, tyramine-, and putrescine-producing lactic acid bacteria in foods.

In a screening of primers, we have selected three pairs of primers for a multiplex PCR assay for the simultaneous detection of lactic acid bacteria (LAB) strains, which potentially produce histamine, tyramine, and putrescine on fermented foods. These primers were based on sequences from histidine, tyrosine, and ornithine decarboxylases from LAB. Under the optimized conditions, the assay yielded a 367-bp DNA fragment from histidine decarboxylases, a 924-bp fragment from tyrosine decarboxylases, and a 1,446-bp fragment from ornithine decarboxylases. When the DNAs of several target organisms were included in the same reaction, two or three corresponding amplicons of different sizes were observed. This assay was useful for the detection of amine-producing bacteria in control collection strains and in a LAB collection. No amplification was observed with DNA from nonproducing LAB strains. This article is the first describing a multiplex PCR approach for the simultaneous detection of potentially amine-producing LAB in foods. It can be easily incorporated into the routine screening for the accurate selection of starter LAB and in food control laboratories.

Amino Acid Sequence↗

Evaluation of Her-2/neu gene status in osteosarcoma by fluorescence in situ hybridization and multiplex and monoplex polymerase chain reactions.

CONTEXT: Previous reports suggest that the human epidermal growth factor 2 (HER-2/neu) receptor may be overexpressed in osteosarcoma. OBJECTIVE: To determine whether osteosarcomas have amplifications of the HER-2/neu gene. DESIGN: We studied a series of osteosarcomas by fluorescence in situ hybridization (FISH) and by 2 real-time polymerase chain reaction assays that measure the amount of HER-2/neu DNA relative to a control gene. The HER-2/ neu monoplex and multiplex assays were capable of identifying those cases of breast cancer that were known to overexpress HER-2/neu as assessed by FISH. We initially studied 21 cases of osteosarcoma by FISH analysis (using a technique that included a probe for chromosome 17), 11 of which had their HER-2/neu gene amplification status previously reported. RESULTS: None of these osteosarcoma cases showed HER-2/neu amplification by our FISH analysis and subsequent quantitative (multiplex) polymerase chain reaction. Apparent expression of HER-2/neu protein was observed in several of the cases but the immunoreactivity was localized to the cytoplasm and was not membranous in character. An additional 35 osteosarcoma specimens were subjected to monoplex polymerase chain reaction analysis, and amplifiable DNA was recovered from 19 specimens (54%). None of these samples had HER-2/neu amplification by monoplex PCR analysis and only one case had membranous immunoreactivity graded as 1+. CONCLUSION: Although a small subset of osteosarcomas had weak noncircumferential membranous immunoreactivity for HER-2/neu protein, no osteosarcomas demonstrated positive (2+ or 3+) immunoreactivity for HER-2/ neu protein and none showed HER-2/neu gene amplification by either FISH or polymerase chain reaction.

Bone Neoplasms↗